Ask HN: When did Claude Fable start giving summarized thinking?

I am on v2.1.245 and I just noticed this morning that I'm getting blocks that look like:

(summarized)

Grey thinking looking text that tells what was done or what Claude considered or confirmed.

I had sessions open last night and I don't remember this. Personally I find this great. Fable would often go dark for long periods of time with the prompts I gave it and then drop a huge wall of text for all the work it had been doing in the background.